A series of four tests was conducted at NASA-Langley Research Center in the Aircraft Interior Acoustic Simulator using a range of stimuli whose spectrum shapes represent a wide selection of recordings made during cruise in a variety of jet aircraft. These stimuli were broadband in nature and did not contain any audible tonal components. Preference rankings were found for ten stimuli in the first test. The succeeding two tests were designed to determine sound level differences equivalent to the preference rankings. The fourth test extended the range of spectrum shapes and again determined preference rankings and equivalent level differences. The rankings were found to spread over a range of four phons for sounds set at equal calculated Loudness Levels. Metrics that predicted this effect, after loudness had been taken into account using Loudness Level, included Blazier's Quality Assessment Index (QAI), a measure of spectrum balance used in room acoustics. The preferred spectral shapes discovered fit well with the spectra suggested by Beranek for background noise in building spaces.
Effects of spectrum shape on subjective preference to broadband jet aircraft interior sounds
Noise Control Engineering Journal ; 50 , 5 ; 160-175
2002
16 Seiten, 26 Quellen
Article (Journal)
English
Online Contents | 2002